But Contractor, a mechanical engineer with a background in 3D printing, envisions a much more mundane—and ultimately more important—use for the technology. He sees a day when every kitchen has a 3D printer, and the earth’s 12 billion people feed themselves customized, nutritionally-appropriate meals synthesized one layer at a time, from cartridges of powder and oils they buy at the corner grocery store. Contractor’s vision would mean the end of food waste, because the powder his system will use is shelf-stable for up to 30 years, so that each cartridge, whether it contains sugars, complex carbohydrates, protein or some other basic building block, would be fully exhausted before being returned to the store.

Ubiquitous food synthesizers would also create new ways of producing the basic calories on which we all rely. Since a powder is a powder, the inputs could be anything that contain the right organic molecules. We already know that eating meat is environmentally unsustainable, so why not get all our protein from insects?

If eating something spat out by the same kind of 3D printers that are currently being used to make everything from jet engine parts to fine art doesn’t sound too appetizing, that’s only because you can currently afford the good stuff, says Contractor. That might not be the case once the world’s population reaches its peak size, probably sometime near the end of this century.

“I think, and many economists think, that current food systems can’t supply 12 billion people sufficiently,” says Contractor. “So we eventually have to change our perception of what we see as food.”

There will be pizza on Mars

The ultimate in molecular gastronomy. (Schematic of SMRC’s 3D printer for food.)(SMRC)

If Contractor’s utopian-dystopian vision of the future of food ever comes to pass, it will be an argument for why space research isn’t a complete waste of money. His initial grant from NASA, under its Small Business Innovation Research program, is for a system that can print food for astronauts on very long space missions. For example, all the way to Mars.

“Long distance space travel requires 15-plus years of shelf life,” says Contractor. “The way we are working on it is, all the carbs, proteins and macro and micro nutrients are in powder form. We take moisture out, and in that form it will last maybe 30 years.”

Pizza is an obvious candidate for 3D printing because it can be printed in distinct layers, so it only requires the print head to extrude one substance at a time. Contractor’s “pizza printer” is still at the conceptual stage, and he will begin building it within two weeks. It works by first “printing” a layer of dough, which is baked at the same time it’s printed, by a heated plate at the bottom of the printer. Then it lays down a tomato base, “which is also stored in a powdered form, and then mixed with water and oil,” says Contractor.

Finally, the pizza is topped with the delicious-sounding “protein layer,” which could come from any source, including animals, milk or plants.

The prototype for Contractor’s pizza printer (captured in a video, above) which helped him earn a grant from NASA, was a simple chocolate printer. It’s not much to look at, nor is it the first of its kind, but at least it’s a proof of concept.

Replacing cookbooks with open-source recipes

SMRC’s prototype 3D food printer will be based on open-source hardware from the RepRap project.(RepRap)

Remember grandma’s treasure box of recipes written in pencil on yellowing note cards? In the future, we’ll all be able to trade recipes directly, as software. Each recipe will be a set of instructions that tells the printer which cartridge of powder to mix with which liquids, and at what rate and how it should be sprayed, one layer at time.

This will be possible because Contractor plans to keep the software portion of his 3D printer entirely open-source, so that anyone can look at its code, take it apart, understand it, and tweak recipes to fit. It would of course be possible for people to trade recipes even if this printer were proprietary—imagine something like an app store, but for recipes—but Contractor believes that by keeping his software open source, it will be even more likely that people will find creative uses for his hardware. His prototype 3D food printer also happens to be based on a piece of open-source hardware, the second-generation RepRap 3D printer.

“One of the major advantage of a 3D printer is that it provides personalized nutrition,” says Contractor. “If you’re male, female, someone is sick—they all have different dietary needs. If you can program your needs into a 3D printer, it can print exactly the nutrients that person requires.”

Replacing farms with sources of environmentally-appropriate calories

Contractor is agnostic about the source of the food-based powders his system uses. One vision of how 3D printing could make it possible to turn just about any food-like starting material into an edible meal was outlined by TNO Research, the think tank of TNO, a Dutch holding company that owns a number of technology firms.

In TNO’s vision of a future of 3D printed meals, “alternative ingredients” for food include:

algae

duckweed

grass

lupine seeds

beet leafs

insects

From astronauts to emerging markets

While Contractor and his team are initially focusing on applications for long-distance space travel, his eventual goal is to turn his system for 3D printing food into a design that can be licensed to someone who wants to turn it into a business. His company has been “quite successful in doing that in the past,” and has created both a gadget that uses microwaves to evaluate the structural integrity of aircraft panels and a kind of metal screw that coats itself with protective sealant once it’s drilled into a sheet of metal.

Since Contractor’s 3D food printer doesn’t even exist in prototype form, it’s too early to address questions of cost or the healthiness (or not) of the food it produces. But let’s hope the algae and cricket pizza turns out to be tastier than it sounds.